Heparin Coated Cardiopulmonary Bypass Circuits in Coronary Artery Surgery - A Clinical Study

Cardiopulmonary bypass with systemic heparinization causes trauma to blood cells and coagulation defects. Artificial surfaces could be coated by end-linkage binding of heparin (Carmeda Bioactive Surface CBAS™). The use of such surfaces during cardiopulmonary bypass in animals resulted in less postoperative blood loss and better preservation of blood cells. Heparin-coated circuits were employed during coronary artery grafting in seven patients (Group C). Concomitantly, the heparin dose was reduced by 25% and an ACT of 300 sec was accepted. An additional seven patients were operated with non-coated circuits (Group NC), requiring an ACT above 400 sec with normal doses of heparin. There was no thrombo-embolic complications in Group C. The postoperative bleeding was generally low and without significant intergroup differences. Coagulation parameters displayed a significantly lower ACT and anti-Factor Xa during bypass in Group 1C. A tendency towards less blood cell trauma was observed with heparin-coated circuits, although the differences did not reach statistical significance. The protamine dose could be reduced by 50%, which significantly reduced the protamine/heparin quotient. This study indicates that routine cardiopulmonary bypass could safely be performed with heparin-coated circuits and reduced intravenous doses of heparin and protamine. It is suggested that the use of heparin-coated circuits may lead to less blood cell trauma.